Choriocarcinoma-like squamous cell carcinoma: a new variant expressing human chorionic gonadotropin

Cutaneous squamous cell carcinoma (SCC) has been classified into a large number of subtypes, which have been grouped according to malignant potential. We describe a new morphological variant containing areas of intermingled cytotrophoblast-like and syncytiotrophoblast-like cells and designate it "choriocarcinoma-like SCC." Furthermore, the neoplasm exhibits expression of human chorionic gonadotropin predominantly in the syncytiotrophoblast-like foci, mimicking the germ cell tumor. Human chorionic gonadotropin expression has been described in SCC from other organs, but not by cutaneous SCC, to our knowledge. This new variant could be misinterpreted as metastatic choriocarcinoma, especially in small punch biopsies. The frequency of this neoplasm and its malignant potential are undetermined.